trail running is not only an endurance event requiring strong aerobic capacity and a built-to-last cardiovascular system — it also has its own specific demands. Climbs and descents are often the heart of a trail and offer stunning scenery, but they also put serious strain on your legs and lungs. Beyond your standard training, specific sessions are needed to work on these two types of terrain. Of course, seasoned trail enthusiasts already know this and will learn nothing new here — but for the many people discovering the sport, here is an overview of a trail training plan you can put into practice.

Specific sessions in a trail training plan: ascents.
This is certainly the most intense effort on a trail. Climbs place particular demands on the thighs and the cardiovascular system. That said, it must be tackled at each person's own level. Some will choose to walk on certain gradients because running them is simply too demanding. At the same pace, heart rate while walking has been shown to be 20 to 30 beats lower than while running — a clear energy saving.
But there are ways to build an effective trail training plan for climbs.
Two types of sessions can be worked on: one focused on intensity and one on endurance, which can also be shared with descent preparation.
Intensity session: the goal is to build muscular strength in the thighs and accustom your cardiovascular sys
tem to intense effort. Choose a relatively short hill that can be climbed in around 2 minutes — pick a reasonable gradient, but not too gentle either. Each week, complete a session of 6 ascents.
of this hill at first, then as the weeks go by, progress to 10 or even 12 ascents. You can also replace this hill with a flight of stairs if you are in an urban environment — climb the steps at a sustained pace, two at a time, walking with a strong push or running. Whether on the hill or the stairs, the descent should always be done by walking at a recovery pace, making sure to breathe well and bring your heart rate back down.
Endurance session: go on short hikes of one to three hours over hilly or even mountainous terrain. Choose a route where you can do long, steady climbs (not necessarily very steep) of around half an hour. Alternate these climbs between a fast walking pace and a moderate running pace.
Specific sessions in a trail training plan: descents.
Descents are 50% mental. Very often, they can be daunting for many beginner runners. The main fault is tension: the thighs quickly lock up under the repeated impact of the descent, and with less balance, the runner can easily fall on the most difficult sections — breathing becomes blocked, muscle oxygenation is ineffective, and what should have been a (partial) recovery phase turns into an ordeal.
Here are a few tips for tackling descents more effectively:
-lower your centre of gravity by staying relaxed through the knees and dropping your hips slightly — as if you were about to sit down. Try to absorb impact with your thigh muscles, avoiding heavy foot strikes. You need to "hold back" the weight of your body so it doesn't crash down with every stride.
-your upper body should stay relaxed. Keep your arms slightly out to the sides for balance. Don't hesitate to use broad arm movements to accompany your motion.
You also need to learn to relax mentally and not hold your breath. Try to be aware of your breathing and "force" it a little — for example, by making a conscious effort to exhale deeply with each stride.
Descent training is often difficult to programme in a targeted way. Make the most of the weekly endurance session mentioned above, during which you can work on long descents. Even if they are not very steep, try to run them at a high pace while applying the tips given — or even exaggerating them slightly. Descent work is also about agility and balance. If you need to work on these specific points, you can do small drills (even on flat ground) — such as moving quickly between cones or jumping from one stone to another as if crossing a river. And remember: the more descents you do without a mental brake, the faster you'll improve!

Specific sessions in a trail training plan: how to train on flat terrain?
Not everyone lives in the mountains or in a hilly enough area to find steep inclines or long enough slopes. So what do you do if you want to train for trail while living in a fairly flat region?
Intensive hill sessions can potentially be replaced by step sessions. For example, do sets of around a hundred double steps at a fairly intense pace. Build up progressively by increasing the number of sets as your training advances. To bring your cardiovascular rate back down, you can finish these sets with a recovery set of around 25 double steps at a fairly slow pace. Ideally, warm up before this session — a light outdoor jog of around 30 minutes works well. These step sessions will also be an excellent cardiovascular complement to your trail training!
You can also use stairs, as mentioned above. I know some people who love training on the stairwells of the office block where they work!
For endurance, choose a long route as described above and add interval training to push your heart rate up. Do very intense bursts of 2 minutes, trying to lift your knees fairly high. You can also use the terrain to your advantage. Even if you live in a completely flat area, you'll always find banks and embankments (grassy slopes, etc.). Don't hesitate to run up them repeatedly at high intensity.
trail running demands a solid training foundation to handle the distance and duration of the effort. But don't neglect the specific work of trail — namely, climbs and descents. The more you work on them in training, the more you'll be ready on race day to take a big dose of pleasure from your route. And that's the whole point, isn't it?